In keeping with the Go Exploring theme, a trip to the Drakesbad Guest Ranch in Lassen Volcanic National Park, should be on your list. People have been going to this place since the 1870s, and there is plenty of hydra-thermal sites nearby such as Boiling Springs Lake and Devils Kitchen. If you want to dine there, you will need to call ahead, and they even make sack lunches for your hiking pleasure.